This invention relates to a tape measure capable to be uncoiled and coiled.
Tape measures, which are stored coiled in a housing and pulled out therefrom for the measuring operation while the tape measure is uncoiled from a reel or the like in the housing, so-called number meters, are well-known. The tape measure, in order to have a certain self-supporting capacity in pulled-out state, in the horizontal plane, is made of metal and has a curved cross-sectional shape.
A conventional tape measure of this kind is self-supporting when the length pulled out is shorter than about 1 m. When the length pulled out is longer, a fold is formed in the tape transverse to its longitudinal direction. When the housing or the tape are treated with slight incautiousness, said self-supporting length is only about 0.5 m. These stated lengths, of course, vary from one case to another. It is, however, a very great disadvantage that the tape cannot be pulled out to its entire length, which most often is 2 m or longer, without giving rise to fold formation in the tape. The said disadvantage implies above all, that measurements of a length exceeding that at which the tape is self-supporting, are carried out with great difficulty.